Masks & suggestions for how to use them

[T. Modesto,PhD]

Re: Masks & suggestions for how to use them

I think we need to see more about the research on al of this. My sense is that there will be a number of suggestions that will be offered by numerous sectors of society in the coming time of this medical disaster. We will need to be using common sense about some of this and common sense and fear / panic are not the same thing - frankly not even kissing cousins! Remember that for many, the need will not be on a regular basis for the use of a mask since most will be self-sheltering and not needing to use the ones that they will hopefully have on stock. Only in populated situations will that be a necessity.

I suggest that we contact OHSA or UP to see what they have to say independently of the information of al sorts that is offered. I appreciate the idea to be offered here for suggestion and I hope we can completely investigate it prior to deciding on the possibility of using it as a resource.
TM

"....a large plastic bag..."

Please do NOT try this.

And remember...do not leave plastic bags around small children.

[sameo416]

Re: Masks & suggestions for how to use them

when one N95 filters 95% then I calculate that two N95
in a row , maybe in a tube, should filter 99.75%.
Or two N100s should filter all except one in a million particles.
Breathing resistence is proportional to the surface of the mask.

So, shouldn't we be able to build mask-systems of any level
of protection ?

The problem with 'layering' masks is twofold. First, breathing resistance is a function of both surface area and density of the filter media. Increasing the number of layers in a mask increases the density of the filter without increasing the surface area, so breathing resistance goes up appropriately.

Second, the fit around the edges of the mask might negate some of the added filter density. If you increase the breathing resistance in the middle of the mask without improving the face seal there is a chance for increased 'blow by'. I would also wonder about how well the edges of the masks would line up, which might increase this problem.

Disposable masks are designed to be used by themselves. Layering could compromise the design.

Rather than focusing on ways to upgrade, perhaps just start out with a better mask. The ultimate in protection would be a full-face respirator with particulate filters. When properly fitted there is next to no leakage and the full-face mask protects against vapour and droplet risks (impinging on the eyes). The breathing resistance also tends to be better depending on the mask design.

Next best would be a half-face mask with catridge filters.

These require some practice to use but it is easily done with an instruction book and some rehersal.

This mask also gives the added benefit of being able to add chemical cartridges such as organic vapour cartridges - these will give you particulate protection as well as protection against some hazardous vapours.

For the general public who need to occassionally walk-about during a possible pandemic I would feel comfortable recommending a disposable N-100 mask and good hand-washing practice. After each trip out the mask should be disposed of outside your residence, followed by good hand washing.

The best defence will always be to limit exposure as much as possible. Even with a mask and gloves the key is to minimize the amount of time in public places.

Higher levels of self-protection would be needed for those who were in deliberate and sustained contact with potentially infectious people. For example, a church group performing outreach to street people during a pandemic would need to consider providing volunteers with training and personal protective equipment (masks, gloves, eye shields, gowns).

[gsgs]

Re: Masks & suggestions for how to use them

this all should long have been tested and known. We know about
influenza since centuries, but not how it spreads and what
interrupts its spread ?!?

For multiple masks in a row we need a different design, but it can
clearly be done. Maybe with these disposable N95 and you can
just put 2 filters in it instead of one ? e.g. North CFR-1 or AOsafety

I'm not sure, how much it helps, though. What goes through one might
also go through both.
For breathing resistance, imagine a long filter formed as a flexible
tube, which can be bended. Make it longer when resistance is big.
Close one end of the tube, attach the other to nostrils or mouth.

[gsgs]

Re: Masks & suggestions for how to use them

"....a large plastic bag..."

Please do NOT try this.

And remember...do not leave plastic bags around small children.

not the head into the bag, if that's your concern.
Just mouth-breath into-from it repeatedly through a small opening.
That should be safe, or not ? Well, I tried it. After a while you
start breathing more and faster. In a severe pandemic you might
prefer it over masks for short shopping or visits.

[sharon sanders]

Re: Masks & suggestions for how to use them

I think we should be open to all ideas, however, this is an international site and many of our visitors who speak other languages and/or who do not have access to an adequate public health system may rely on us for valid suggestions.

gsgs- I am glad that you cleared up the point about putting the head in a plastic bag. In no circumstances is this acceptable.

Never put your head in a plastic bag.

[yielddude]

Re: Masks & suggestions for how to use them

with the nanomasks, wasn't that all fraud ?
I think, I read something like this about emergency filtration products.

Searching google... I just found this board:
http://ragingbull.quote.com/mboard/b...cgi?board=EMFP

haven't read it yet...

The nanomask is not a fraud. However, it does not yet have any regulatory approvals. It has been independently tested in labs, but until it receives FDA or NIOSH approval, it will not achieve "universal" acceptance.
The mask/filters were submitted to the FDA for approval as a class II medical device, and the company is basically waiting for approval before trying to proceed with any commercial transactions. Until this is resolved, the company is more or less in standby mode.
They did get aqpproval from the Australia regulatory agency in August (TGA), however there was a subsequent issue that arose, and they are now also trying to get that resolved.
Most think the FDA question will not be resolved until Dec. 20th at the earliest (this would be 3 months from FDA submission).

Regards,
yield

[DeadAhead]

Re: Masks & suggestions for how to use them

It should be noted that N95s, EVEN IF FITTED PROPERLY, do NOT reliably block viral particles.

The current strain of the H5N1 virus, or avian flu, is approximately 0.1 micron (100 nm) in size.

Examples of particle size:

Viruses 0.02 to 0.3 microns - N95 mask not effective
Bacteria 0.5 to 10 microns - N95 mask effective
Mold spores 1 to 70 microns - N95 mask effective
Fungi 2 to >200 microns - N95 mask effective

Best, DA

[sameo416]

Re: Masks & suggestions for how to use them

It should be noted that N95s, EVEN IF FITTED PROPERLY, do NOT reliably block viral particles.

The current strain of the H5N1 virus, or avian flu, is approximately 0.1 micron (100 nm) in size.

Examples of particle size:

Viruses 0.02 to 0.3 microns - N95 mask not effective
Bacteria 0.5 to 10 microns - N95 mask effective
Mold spores 1 to 70 microns - N95 mask effective
Fungi 2 to >200 microns - N95 mask effective

Best, DA

All true.

I have not seen any research suggesting that individual viral bodies can become airborne (any comments from those with medical backgrounds?). Pathogens are usually transmitted attached to droplets or dust sized in the 1-10 micron range, which is why N95 masks are used in hospitals for infection control both ways (patient <-> caregiver) and against viral and bacterial threats. Even 'weaponized' pathogens used as biological warfare agents are in the 1-5 micron range.

Also recall that '95' means 95% effective, so the mask will let through 5% of particles 0.3 microns or larger even though it is rated for that size of threat.

This is the reason why anyone working with known nasty pathogens will wear self-contained breathing apparatus. Your own clean air supply is the only way to ensure the lowest chance of infection. The CDC recommends the minimum level of protection (this is in a biological warfare situation) as a full-face mask with P-100 or HEPA filter but only if no aerosol production is present. http://www.bt.cdc.gov/DocumentsApp/A...001Protect.asp

[Sisterobin]

Re: Masks &amp; suggestions for how to use them

Can anyone tell me at what temperature does the BF virus die? Is it possible to 'bake' a paper or cloth mask at a low temperature {say 150 or 165 degrees} or pressure can it like an auto clave to kill the germs? Or perhaps a food dehydrator? They can reach those temperatures.

I know this is a bit 'out' there, but in reading all the posts on FT I've not found this subject addressed.

Sisterobin~

[DRJJ]

Re: Masks &amp; suggestions for how to use them

Three questions

through second-hand contact of a contaminated surface or person (and then through the skin by a cut or cross-contamination of a mucus membrane).

1 What is the danger of contamination through vaginal mucus membrane through toileting activities for females?

2. Should we include razor blades in emergency preparedness kits for shaving, so that masks may be fitted to male faces properly?

3. Can used masks be rendered safe with exposure to several days of sun or saturation in bleach solution?

[Laidback Al]

Re: Masks &amp; suggestions for how to use them

Three questions
..... 2. Should we include razor blades in emergency preparedness kits for shaving, so that masks may be fitted to male faces properly?

That is an excellent suggestion. Generally, most face masks on men with full beards do not pass the fit test and seal safely.

Three questions
..... 3. Can used masks be rendered safe with exposure to several days of sun or saturation in bleach solution?

Short answer - No.

see:

http://www.flutrackers.com/forum/showthread.php?t=5342


and

The effectiveness of a face mask decreases as the mask material becomes saturated, so re-use or extended use is not wise if you are in a contaminated environment. This is exacerbated if you are wearing a mask in a cold environment as there is increased condensation on the mask material. There are N95 type masks with an exhaust vent that protects the filtering surfaces from compromise by moisture. (I've worn N95 masks outdoors in the Canadian winter and had most of the filter surface blocked by frost in short order)

The WHO recommends changing surgical type masks every two hours and N95 masks every 6-8 hours. (http://www.wpro.who.int/sars/docs/masks/masks_faq.asp)

from thread: http://www.flutrackers.com/forum/showthread.php?t=12144

[sameo416]

Re: Masks &amp; suggestions for how to use them

Laidback Al has got it right.

An info sheet on the preparation for a fitting of an N95 mask:

http://www.orcbs.msu.edu/biological/...al/n95_fit.pdf

They state that even one day's growth of facial hair can impair the sealing of an N95 type mask. You can tolerate more facial hair with a half- or full-face respirator but it can still compromise the seal. The razor idea is a great one - if you're in a life-threatening situation the loss of some beard is probably a good trade-off.

A further consideration for the re-use of disposable masks is the danger of increasing the risk of infection. If you re-use a mask in a contaminated environment pathogens will become concentrated within the filter material. Once the filter material is damp from moisture in the wearer's exhaled breath, it can also provide a suitable growth media for some pathogens. This could lead to a mask user breathing through a higher concentration of pathogens than would otherwise be present, and potentially increasing their risk of infection.

In trying to 'clean' a disposable mask you would need a technique that could neutralize pathogens contained within the rabbit warren of air passages in the filter material. Contaminents do not rest only on the outer surface, but are distributed through the filter media - the filter works by providing twisting paths that make it difficult for particles to penetrate. I'm not aware of any process that would achieve this (steam autoclaving maybe, but how would this affect the filter material?).

Also, once you've worn a mask for a period of time dust in the air begins to increase the breathing resistance by blocking some of the air pathways. This tends to increase filter efficiency (good) but the increased resistance also causes more leakage (bad).

They're disposable masks for a reason. These same comments apply to all air-purifying filters whether on a disposable N95 mask or in a canister filter attached to a full-face respirator.

[sharon sanders]

Re: Masks &amp; suggestions for how to use them

Thanks everyone for a great discussion on masks.

[Jonesie]

Re: Masks &amp; suggestions for how to use them

Wearing nylon hosiery over a surgical mask essentially eliminates the face leakage, making this combination a practical, albeit macabre, alternative. The less comfortable N95 respirators would probably result in lower compliance.

That's amusing. I mentioned in a really old post...a year or more ago,, as a joke, to pull a nylon stocking over the face to hold down a mask. I never thought someone would take the ball and run with it!

Actually. if stuck with just a surgical mask, use micropore tape to tape it to the face. then you have better protection and close the gaps.

But then. if the tape refuses to stick, an old nyon might be a good alternative.
Red fishnet stockings might be sexier and less macabre, but probably won't work as well at closing gaps..

Micropore tape is better than wearing a nylon stocking over your head, alarming the public, and being chased around by cops wherever you go!

3M makes the tape:

http://www.qualitymedicalsupplies.com/page/QMS/CTGY/73-MP

[Lynda]

Re: Masks &amp; suggestions for how to use them

Wow. There's a lot of misinformation here.

Once a mask begins to break down, it begins to get horizontal collapse which alters the fit, rendering it useless.

Viruses can live much longer than that on environmental surfaces, especially in the cold.

Anyone who has ever worn a Nano knows that they don't even come close to fitting, even if they did work, and there's absolutely no reason to think they do work. All research is private, paid for by them. In fact, they recently changed the shape, admitting that the old shape was a problem. So what about the millions of masks already sold at a HIGH price? If BF comes, the people depending on those masks will be exposed. They are genius marketers.

DEPARTMENT OF HEALTH & HUMAN SERVICES Public Health Service
__________________________________________________ ______________________________________
June 29, 2006
NIOSH RESPIRATOR USERS NOTICE: CAUTION
Subject: Misleading representation of the Nano Guard Particulate Respirator as a NIOSH Approved N-95 Respirator

It has been brought to the attention of the National Institute for Occupational Safety and Health (NIOSH) through the process of a product audit, that 2HDistributors is representing and selling a Particulate Respirator called Nano Guard as a NIOSH approved respirator.

The Nano Guard respirator is individually packaged and improperly labeled with the NIOSH and Department of Health and Human Services logos. Additionally, the label contains a NIOSH approval number, TC-84A-4175, which was not issued to 2HDistributors.

The Nano Guard package label is illustrated below.

A NIOSH approval is issued to a respirator only after it has been evaluated in the laboratory and found to comply with all the requirements of Title 42, Code of Federal Regulations, Part 84, including a review of the manufacturers quality plan.

The Nano Guard N95 Particulate Respirator is not certified and approved by NIOSH.

Sincerely yours,
Heinz W. Ahlers
Chief, Technology Evaluation Branch
National Personal Protective Technology Laboratory
Centers for Disease Control
and Prevention (CDC)
National Institute for Occupational
Safety and Health (NIOSH)
National Personal Protective
Technology Laboratory (NPPTL)
P.O. Box 18070
Pittsburgh, PA 15236-0070
Phone: 412-386-4000
Fax: 412-386-4051
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